Particularly in the field of large-diameter bearings, for example large-diameter rolling bearings such as slewing bearings adapted to be used in wind turbines, tunnel boring machines, cranes, ladle turret, marine thrusters, stacker reclaimer, it is known to use segmented cages which comprise segments abutting circumferentially and having pockets for receiving the rolling elements. Each segment comprises a plurality of adjacent pockets, each pocket receiving one or several rolling elements.
Currently, such a segment with pockets receiving each several rolling elements is metallic and made from typically from brass. Such a segment with pockets receiving each only one rolling element is metallic (brass) or made from synthetic material.
Known segments are massive and heavy, in particular the ones made from metal.
Known segments can be obtained by different several manufacturing processes, including molding, injection molding, sand molding or machining.
Injection molding is the preferred manufacturing process for a segment made from synthetic material, but due to the large dimensions of the segment and its current geometry, it is not easy to inject synthetic material uniformly in the mold, and unfortunately sometimes bubbles of air are trapped in the segment, which degrades its mechanical properties. Also, still because of different geometrical thicknesses of portions of the segment, the shrinkage occurring during the cooling of the injected material is not uniform and lead to deformation of the segment or even sometimes its breakage.
Such a difference of thickness is present in a known segment illustrated on FIG. 1. The segment comprises an inner wall and an outer wall extending circumferentially (not represented) and radial beams 27 which connect together the inner and outer walls. Each radial beam comprises a central portion 27a and two opposite end portions 27b, 27c. At least one end portion 27b, 27c cooperates with one rolling element 9 to center the segment onto the rolling elements. The end portions are wider than the central portion, which indeed constitutes a difference of thickness, in the circumferential direction, of the radial beam.
The above situations induce scraps and untimely deteriorations and are not satisfying.